If you have, in fact, mistakenly formatted the system disk, there may be recovery utilities you can burn to a bootable CD/DVD that include an unformatter. I've never used an unformatter, so I can't vouch for quality or effectiveness.
If you were running Windows 10 all you need to do is download the Windows 10 installation ISO file and burn it to a DVD, or a bootable USB key.
AFAIK, all windows 10 computers register a hash of certain unique identifiers with Microsoft, and when your computer goes to "Activate" Microsoft will match the hash with the one it stored when Lenovo installed the OS, (or you upgraded from 7/8 to 10) and you're off and running.
Any data and applications however will be lost if you reinstall windows.
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Please help me..
crwdns2934271:0crwdnd2934271:0 Asif shaikh crwdne2934271:0
have you any usb storage plug in, also you need to change the boot menu in bios and have the windows file to boot, so if you have windows on usb you have usb at the top of the list or disk to boot first. make sure you have the write windows like 32 or 64 bit
crwdns2934271:0crwdnd2934271:0 daniel crwdne2934271:0